Quick-acting closure for an endoscope

ABSTRACT

The invention relates to an endoscope comprising a first quick-acting closure ( 3 ) for a traction wire ( 13 ) of a Bowden wire device, which closure is arranged at the proximal end to be pivotable or displaceable, with a locking position of the quick-acting closure ( 3 ), in which an attachment unit for loosening and attaching the traction wire ( 13 ) of the Bowden wire device can be actuated and with a working position of the quick-acting closure ( 3 ), in which the attached traction wire of the Bowden wire device can be displaced within a working area which is defined by end positions ( 15′, 15 ″) of the quick-acting closure ( 3 ), in order to actuate a mechanism which is arranged at the distal end of the endoscope together with the traction wire ( 13 ) of the Bowden wire device in such a way that it can be loosened.

The invention relates to an endoscope, particularly a flexible endoscopewith the features of the preamble of claim 1.

Endoscopes of this kind, for example duodenoscopes, whose lens isusually arranged at the side of the endoscope head, comprise amechanism, in particular an Albarran mechanism with an Albarran lever,which makes it possible to move the probes, which are introduced intothe endoscpoe through the working channel thereof, in the angle of viewof the lens. The Albarran lever can be moved by means of a Bowden wiredevice extending between the distal and the proximal ends via anoperating lever arranged at the outside of the endoscope's housing.

In commonly known endoscopes of the type described in the document U.S.Pat. No. 4,198,959, the Albarran mechanism or the Albarran lever is afixedly integrated component of the endoscope head, and the sheathing ofthe Bowden wire device is embodied as a channel in the endoscope'sintroduction shaft and housing, which is sealed off from the inside ofthe endoscope. The traction wire of the Bowden wire device extendingtherethrough is usually sealed off from the outside at the distal andthe proximal ends of the Bowden wire device with the aid of sealingrings. As these seals are seals through which a movable wire extends, atleast the distal end may be contaminated as a result of pulling a pieceof wire which is soiled e.g. with blood to the inside when an endoscopeof this kind is used. Endoscopes or heads of endoscopes soiled in such amanner are difficult to clean and, when used again, lead to problemsregarding hygiene or to spreading of germs and to increased sluggishnessof the Bowden wire device or of the entire operating mechanism of theAlbarran lever.

In another type of endoscope, the Bowden wire device can be irrigatedfor cleaning purposes through an opening for a syringe at the proximalend thereof. During irrigation, the liquid can emerge at the distal endof the Bowden wire device, which is not sealed. In case of inexperthandling, however, some of the irrigation liquid may leak into theinside of the endoscope as a result of too high pressure exerted on theinner seals. Mostly, such cases occurring in practice result fromalready existing contamination which causes a reduction of thecross-section of the channel to be irrigated and thus a lower rate offlow; here, the maximum permissible pressure may easily be exceeded ifthe operating personnel exerts too much pressure on the syringe. As aconsequence of this, the endoscope will have to be repaired, which isboth time-consuming and expensive.

Furthermore, both these known types share the disadvantage that theAlbarran mechanism is difficult to clean because of the fact that it isintegrated in the instrument. In practice, this mechanism has to becleaned with a small brush, and it turned out that damage to thedelicate Albarran mechanism is often caused thereby. Moreover, becauseof the integrated construction of the Albarran mechanism, any necessaryrepair thereof is time-consuming and expensive, as the entireencapsulated head, which also includes the lens, has to be exposed and,after the Albaran mechanism has been repaired, the head has to beencapsulated again.

In another endoscope known from the document JP Sho 62 42 606, theAlbarran mechanism can be screwed off the endoscope head and can beremoved after the traction wire of the Bowden wire device has beenreleased at the proximal end by loosening a screw connection. After adistal stop plate has been loosened by screwing it off, the sheathing ofthe Bowden wire device can be pulled out.

This kind of loosening of the connection, however, requires technicallyskilled personnel—for reasons of liability, this is usually even done bya maintenance engineer of the company that produces the endoscope—, assuch complex loosening of the connections can neither be expected fromunskilled operating personnel such as a doctor's assistant nor can it bedone by him or her.

If this endoscope should not have any seals to ensure that nocontaminating material will enter at the distal end thereof, theendoscope would have to be cleaned after each use by loosening all theabove-mentioned connections. As it is necessary to have this done bytechnically skilled personnel, this type of cleaning is complicated,expensive and time-consuming, and is thus not practical in medicalworking routine.

This problem was solved by an endoscope described in the document DE 19627 016 C1; here, a support device for the Albarran mechanism can beremoved from the head of the endoscope in the longitudinal direction bythe operating personnel by loosening a quick-acting clamping device forthe traction wire of the Bowden wire device, so both the support device,the traction wire of the Bowden wire device, the sheathing of the Bowdenwire device, and the channel of the Bowden wire device can be cleanedeasily by the operating personnel.

In practice, however, it turned out that a quick-acting clamping devicewhich did not exist in known prior art was difficult to realize, as thenecessary accuracy when moving a mechanism located at the distal endrequires that the working area of the distal mechanism and the operatingmechanism at the proximal end for this purpose always remains the same,irrespective of the number of loosening and attachment actions.

Thus, the object of the present invention is to provide an endoscopewith a quick-acting clamping device which guarantees the requiredaccuracy when moving a mechanism located at the distal end irrespectiveof the number of loosening and attachment actions, including the removalof the distal mechanism, pulling out the traction wire of the Bowdenwire device and the sheathing thereof by the operating personnel, andeasy loosening of the mechanism located at the distal end for cleaningpurposes by the operating personnel.

According to the invention, this object is achieved by the features ofclaim 1.

By providing a quick-acting clamping device in the form of aquick-acting closure, with a locking position for loosening andattaching the traction wire of a Bowden wire device by means of anattachment unit, it is ensured that the attachment is always effected inthe same exact position regarding the longitudinal displacement of thetraction wire of the Bowden wire device. Hereby, the working area forthe entire operating mechanism (both proximal and distal) for amechanism to be operated, particularly an Albarran mechanism, remainsthe same at the distal end irrespective of the number of previousattachment and loosening actions.

At the same time, by providing a second quick-acting closure, it ispossible for the operating personnel to easily remove the mechanismlocated at the distal end and to pull out the traction wire of theBowden wire device. Thus, each time the endoscope has been used, it caneasily be cleaned as necessary by the operating personnel. For thispurpose, by loosening the first and the second quick-acting closures,the endoscope can quickly and easily be disassembled into the componentstraction wire of the Bowden wire device and distal mechanism; due to thefact that sealing elements are not necessary, all the contaminated partsas well as the inner space of the sheathing of the Bowden wire devicecan easily be cleaned by the operating personnel themselves, using e.g.effective cleaning and—as the case may be—sterilization methods such asultrasonic waves, an autoclave, etc.

Furthermore, in case of wear, damage, etc., the Albarran mechanism caneasily be replaced with a new Albarran mechanism by the operatingpersonnel, potentially with further developments of Albarran mechanismsor other types thereof, without a time-consuming and expensivedisassembly of the endoscope head and the proximal end of the endoscopeby a technician being necessary.

If an individual channel of the Bowden wire device is formed inside theendoscope, as described in the document DE 196 27 016 C1, it is possibleto additionally pull out the sheathing of the Bowden wire device and thetraction wire of the Bowden wire device either at least partially orentirely. This further facilitates and improves the loosening of theAlbarran mechanism and the support device and thus the cleaning of theBowden wire device because now, with the separable connection for thetraction wire of the Bowden wire device at the proximal end in the formof a first quick-acting closure, the entire Bowden wire device, i.e. thetraction wire of the Bowden wire device and the sheathing thereof, canbe pulled out either together or one after the other by at least acertain length or even completely.

Here, it is advantageous if, as described above, the sheathing of theBowden wire device is not fixedly attached to the endoscope at theproximal and/or the distal end thereof, e.g. by a screwconnection—although this is possible in principal—, but only limited inits movement in the longitudinal direction via a proximal and a distalstop, respectively. Here, the detachable support device may form thedistal stop, so after loosening the traction wire of the Bowden wiredevice by the first quick-acting closure and after removing the supportdevice by loosening the second quick-acting closure, it is possible topull out not only the traction wire of the Bowden wire device, but alsothe sheathing of the Bowden wire device at the distal end in thelongitudinal direction.

In an embodiment of the invention, the Albarran mechanism is located ina support device, which may be configured e.g. as a slide. This slidecomprises guide elements which cooperate with complementary elements atthe head of the endoscope in such a way that they prevent a lateralmovement, i.e. perpendicularly to the direction of movement of thetraction wire of the Bowden wire device. These guide elements may e.g.be configured as cylindrical projections which engage correspondingrecesses at the head of the endoscope in the longitudinal direction,i.e. the direction of movement of the traction wire of the Bowden wiredevice. These projections may also be hollow cylindrical extensions ofthe channels present in the head of an endoscope, such as the channel ofthe Bowden wire device and/or the working channel for instruments to beintroduced, which engage recesses in the distal end of the channelswhich have a correspondingly enlarged inner periphery. Of course,lateral guides extending in the longitudinal direction, such as adovetail guide, are also conceivable. Advantageously, wrong insertion bythe operating personnel and corresponding damage caused are avoidedthereby, as the direction of insertion, which has to be effectedsubstantially in the longitudinal direction because of the relativelyrigid traction wire of the Bowden wire device, is predetermined thereby.

In a further embodiment of the invention, both the movement of thesupport device and the movement of the sheathing of the Bowden wiredevice in the longitudinal direction are prevented after insertion bythe second quick-acting closure, having e.g. the form of a snap-fit orlocking closure. Hereby, even in case of a sheathing of the Bowden wiredevice which is only fixed in the longitudinal direction in the form ofproximal and distal stops or which is fixedly connected with theendoscope, it is possible to achieve an exact position of the tractionwire of the Bowden wire device after insertion, with the Albarranmechanism or the Albarran lever being in its inoperative position. Thisinoperative position is reached automatically when the traction wire ofthe Bowden wire device is introduced into the sheathing of the Bowdenwire device, due to the back pressure produced in the direction of thedistal end; however, it can also be supported by a correspondingrestoring spring at the Albarran lever.

In addition to the improved loosening of the Albarran mechanism and thesupport device and in addition to the advantages resulting therefrom,this embodiment of the invention also guarantees easier cleaning of theBowden wire device and the channel of the Bowden wire device and of theareas which are otherwise very difficult to keep hygienically clean andsterile by the operating personnel, which cleaning has to be effectedeach time the endoscope has been used for reasons of hygiene.

In a further embodiment, the proximal end of the traction wire of theBowden wire device is stiffened e.g. by soldering or by brazing, withoutincreasing the outer periphery thereof. Advantageously, due to theincreased resistance to pressure, this helps to avoid that the effect ofattachment in the first quick-acting closure is impaired e.g. bysqueezing, fraying out or destroying the end of the wire in any otherway, without an undesired increase in the inner diameter of thesheathing of the Bowden wire device and also of a potentially existingadditional channel of the Bowden wire device being necessary forintroducing the traction wire of the Bowden wire device from the distalend.

In an advantageous embodiment of the invention, the arrested lockingposition and loosening or connecting the traction wire of the Bowdenwire device with the first quick-acting closure can be achieved oreffected simultaneously by means of a single operating element. For thispurpose, the operating element is configured e.g. as a turning knobwhich comprises a characteristic guide line effective in thelongitudinal direction and, in a plane perpendicular to this direction,an attachment mechanism affecting the wire for arresting. The attachmentmechanism may be configured as an eccentric or cam rotatable in thisplane, which affects the proximal end of the traction wire of the Bowdenwire device directly or via a lever which has been prestressed by theforce of a spring. Here, the characteristic guide line may be configurede.g. as a recess extending at the outer periphery and tapering in thedirection of rotation towards the locking position, which cooperateswith a peg which is fixedly arranged at the endoscope. By contrast, theend position “working area” in the opposite direction of rotation isformed by an opening which widens this recess in the longitudinaldirection so that a peg fixedly arranged at the endoscope can be pivotedinto the characteristic guide line or out of the same through thisopening.

In a particularly advantageous embodiment of the invention, thequick-acting closure, which is configured e.g. as a pivotable flap, canbe pivoted in one direction opposite to the distal end and beyond theworking area, with the result that the traction wire of the Bowden wiredevice will slip through in the attachment unit by the length of thispivoting movement.

This may serve to exert a higher prestress onto the Bowden wire devicein the direction of pushing if the shaft of the endoscope is in aposition in which it is entwined and bent to a large extent, resultingin an imperfect restoring effect of the Albarran mechanism in itsinoperative position. Thus, advantageously, the reduced working areaoccurring in known endoscopes in this position can be compensated, sothe function and the mobility of the Albarran mechanism are not limitedeven in such a position. Instead of the action of slipping through, itis of course also possible to loosen the attachment unit in thequick-acting closure and to close it in a position differing from theformer position or in a locking position, as described above. This makesit possible to, in a way, grasp the traction wire of the Bowden wiredevice again in both directions during an operation, so it isadvantageously possible to react on working areas changed by extremesituations.

If the quick-acting closure which is arranged on the outside or is atleast accessible from outside is pivoted in the longitudinal directionof the traction wire of the Bowden wire device, which means that it ismerely displaced, the end of the traction wire of the Bowden wire deviceis advantageously not additionally subjected to a bending load. Thus, apotential breakage of the end of the traction wire of the Bowden wiredevice, particularly of a stiffened end, can be prevented.

If the quick-acting closure is configured as a clamping device which isdisplaceable in the longitudinal direction of the traction wire of theBowden wire device, e.g. in the form of a slide with a clamping gripperwhich can be clamped or can be opened and closed by a clamping element,the end of the traction wire of the Bowden wire device is subjected to aforce acting to the inside in an area within the clamping gripper fromseveral sides distributed over the periphery or along the entireperiphery or is clamped thereby. This has the advantage that damageresulting from a deformation or squeezing of a too small area or spotand/or a deformation of the cross-section of the traction wire from oneside can be avoided.

What all the embodiments according to the invention have in common areadvantages such as the exertion of a prestress, i.e. the change of theworking area and the improved possibilities of cleaning by looseningand, as the case may be, disassembling of the quick-acting closures,removing the head of the endoscope and/or pulling out the Bowden wiredevice and, as the case may be, disassembling the same, and even acomplete disassembly of all these parts by the operating personnel.Furthermore, the operating personnel themselves can easily attend to themaintenance, repair and exchange of individual parts, which couldformerly only be done by a technician.

Further advantageous embodiments of the invention are apparent from thesubclaims.

In the following, the invention is described in greater detail with theaid of embodiments illustrated in the drawing, in which:

FIG. 1 shows a side view of a proximal end of an endoscope with aquick-acting closure;

FIG. 2 shows an enlarged view according to FIG. 1 with the quick-actingclosure in various positions;

FIG. 3 shows a rear view according to FIG. 1;

FIG. 4 shows an individual illustration of a flap of a quick-actingclosure without a lever mechanism in a view X according to FIG. 3;

FIGS. 5a-e show different views of a turning knob of a quick-actingclosure;

FIG. 6 shows a perspective view of a distal end of an endoscope;

FIG. 7 shows the distal end of an endoscope according to FIG. 6, withthe support device being removed;

FIG. 8 shows a side view of a proximal end of an endoscope with adifferent embodiment of a quick-acting closure, in partial section;

FIG. 9 shows a side view of a proximal end of an endoscope according toFIG. 8 without a control mechanism;

FIG. 10 shows a cross-sectional view along the line I-I′ in FIG. 8 and

FIG. 11 shows a side view of a proximal end of an endoscope according toFIG. 8 with an irrigation cap put thereon.

The proximal end 1 of an endoscope, particularly a duodenoscope having aflexible endoscope shaft shown in FIG. 1, comprises a quick-actingclosure 3 at the face thereof; in the lower portion thereof, thisclosure is pivotally mounted on the housing of the endoscope via an axle7 e.g. in the form of one continuous shaft or two individualnon-continuous bolts or screws. This quick-acting closure 3 in the formof a pivotable flap can be pivoted about the axle 7, which isperpendicular to the plane of the drawing, between a starting positionand an end position by a lever mechanism which is pivotably connectedwith the closure in the upper portion of the quick-acting closure 3. Inthis way, a traction wire 13 of a Bowden wire device leading to thedistal end, which traction wire is secured in the upper portion of thequick-acting closure, is displaced in its longitudinal directionperpendicular to the axle 7 and its rotational axis 7′ in order to pivota mechanism which is arranged at the distal end and is connected withthe traction wire of the Bowden wire device, e.g. an Albarran lever 41(FIG. 7), from its inoperative position into a working position.

The pivoting movement of the quick-acting closure from one end position15′ into another end position 15″ is illustrated with a dashed line,respectively, in FIG. 2 as compared to the locking position which isillustrated with a normal line like in FIG. 1. Here, an operating lever19 which is fixedly arranged at the housing of the endoscope in the areaof a control mechanism 5 (shown in FIG. 1) for the movement of theflexible shaft and is rotatable about an axis that is perpendicular tothe plane of the drawing, and which is pivotably connected with thelever 11 that is received at the quick-acting closure 3 so as to berotatable about an axis that is perpendicular to the plane of thedrawing, too, can be moved from a position 19′ to a position 19″ by theoperating personnel until the end position 15′, 15″ of the quick-actingclosure is reached.

As apparent from FIG. 3, a proximal end of the traction wire 13 (shownin FIG. 1) of the Bowden wire device is attached or loosened via a levermechanism located in the upper portion of the quick-acting closure 3.This lever mechanism consists of a T-shaped lever 21 which is mounted inthe quick-acting closure 3 in the plane of the drawing such that one endof its horizontal leg is pivotable about an axis that is perpendicularto this plane by means of a shaft or screw 23. At the opposite end ofits horizontal leg, a restoring spring engages in a manner not shown ingreater detail, whose other end is fixedly connected with a point 25 ofthe quick-acting closure 3 lying in an area beneath this lever (see FIG.4).

As illustrated in FIG. 3, an opening or hole 27 for the proximal end ofthe traction wire 13 of the Bowden wire device exists in thequick-acting closure 3 in the narrower portion of the fulcrum 23 of thelever 21, so the opening 27 lying in a plane perpendicular to the planeof the drawing is intersected by a lower edge of the lever 21 in thecloser portion of the fulcrum 23. The line of direct connection betweenthe fulcrum 23 and the hole 27 is markedly shorter than the line ofconnection between the fulcrum 23 and the working point of the restoringspring, whereby a lever action is created. In this way, as a result ofthis lever action, a force is exerted on an inserted end of a tractionwire 13 which is larger than the restoring force of a spring arranged atthe other end, so the traction wire 13 of the Bowden wire device in theopening 27 is clamped by the lever 21 in cooperation with the opening 27through a front wall 43 and a rear wall 45 of the flap lying in one axis(FIG. 4). Of course, it is also conceivable that the lever 21 isarranged on the outside of the flap instead of being arranged betweenthe front and the rear walls 43, 45 of the flap as in the embodimentserving as an example. In this case, however, the clamping effect on thetraction wire 13 of the Bowden wire device is reduced because thetraction wire is not clamped at two transitional portions any more,namely, the ones formed by the rear wall 45 and the lever 21 and by thelever 21 and the front wall 43, respectively, but at one transitionalportion only.

The pivoting movement of the lever 21 is performed by an operatingelement in the form of a turning knob 29, which is pivotally mounted inthe upper portion of the quick-acting closure beneath the lever 21 in adirection perpendicular to the plane of the drawing; the knob comprisesan eccentric or cam 33 in the area of the lever 21 in the axis ofrotation which is perpendicular to the plane of the drawing (FIG. 3),with the cam being fixedly arranged on the shaft of the turning knob 29.The peripheral surface of this cam 33 communicates with the lower end atthe face of the lever 21, i.e. the vertical leg thereof, so when the cam33 is rotated via the turning knob 29, the lever 21 can be swivelledfrom a lowermost to an uppermost position in the plane of the drawing(FIG. 3).

In the lowermost position shown in FIG. 3, in which the cam contacts thelever 21 with its smallest radius, the opening 27 is covered by thelever 21 and the traction wire 13 of the Bowden wire device is clampedthereby as described. Here, it is also conceivable that the cam 33 doesnot contact the lower face of the lever 21 with its peripheral surfaceany more. However, if the cam 33 is moved by the turning knob 29 into aposition in which its peripheral surface contacts the lower face of thelever 21 with a larger or even the largest radius, the lever 21 isdeflected from the position described, whereby the opening 27 isexposed, so that the proximal end of a traction wire 13 can beintroduced into or pulled out of the same.

The traction wire 13 of the Bowden wire device can both be attached andclamped in the position of the quick-acting closure 3 illustrated inFIG. 1. In order to securely ensure that this position remains fixed, arecess is provided at the outer periphery of the turning knob 29, whosewidth in relation to the axis of rotation decreases towards an end pointand which has a uniform depth, with this recess having the form of avolution 35 shown in FIG. 5a. At its starting point, this volutioncomprises an entrance in the form of an opening, so it opens to theunderside of the turning knob 29.

At its thinnest end position, the volution 35 has a thickness whichroughly corresponds to the diameter of a peg 31 fixedly arranged at thehousing of the endoscope, with the peg engaging the volution in itsplane, i.e. the plane of the drawing according to FIG. 3, in a lockingposition of the quick-acting closure 3.

The opening 37 (shown in FIG. 5b of the volution 35, however, issomewhat larger than the diameter of the peg 31 so that the peg can beintroduced into the profile of the volution more easily and a movementof the flap between the end positions 15′ and 15″ can be ensured in aworking position of the turning knob 29 with the traction wire 13 of theBowden wire device being clamped. As apparent from FIG. 5b, the entranceopening can be widened towards the underside of the turning knob 29 inorder to introduce the peg 31 more easily.

As can be seen from FIGS. 5a and 5 c, the profile of the volutionextends over a 180° portion of the outer periphery of the turning knob29, with other portions—e.g. from 60° to 360°, being conceivable, too.The size of the portion only depends on the cooperation with the cam 33and additionally, as the case may be, on the operating convenience.Depending on the point at which the peg 31 engages the entrance of theprofile of the volution, the cam has to contact the lever 21 at thelower face thereof with its smallest radius in order to clamp the end ofthe traction wire 13 of the Bowden wire device and to ensure a freepivoting movement of the quick-acting closure 3. However, at the pointat which the peg 31 engages the thinnest portion of the profile of thevolution, the cam has to contact the lower face of the lever 21 with itslargest radius in order to particularly ensure that, when thequick-acting closure is arrested in its locking position (FIG. 1), thewire 13 is introduced and clamped at a predetermined invariableposition. For this purpose, as illustrated in FIG. 5a, the volution maycomprise a larger portion 35, e.g. 90°, of the smallest thickness withinwhich the wire 13 is released via the cam 31 and the lever 21 until itis clamped thereby, with the quick-acting closure 3 being fixed orarrested in its locking position as a result of the engagement of thepin 31 in this portion 35 without any clearance.

This has the advantage that an operating error, such as clamping thetraction wire 13 of the Bowden wire device in a wrong position of thequick-acting closure 3 resulting in a limited or wrong working area forthe mechanism at the end of the endoscope which is to be actuated viathe Bowden wire device, e.g. an Albarran lever 41 (shown in FIG. 7), canbe avoided.

As apparent from FIG. 2, the predetermined locking position of thequick-acting closure does not correspond to its end position 15′, but toa position (FIG. 1) which is slightly remote from this end position 15′in the embodiment serving as an example. In this way, a small prestresscan be exerted on the Bowden wire device in order to compensate e.g. asmall clearance that might be present between the traction wire 13 ofthe Bowden wire device and the sheathing of the Bowden wire device, asit might otherwise happen that an end position of the mechanism at thedistal end in the direction of pushing cannot be reached. The resultinggreater length of the traction wire 13 in the Bowden wire device can becompensated in the other end position 15″, i.e. in the direction ofpulling, by the small displacement thereof in the direction of pullingand the working area slightly widened thereby.

In some cases of application, the flexible endoscope shaft has to bebent and/or twisted in such a way that the friction between the tractionwire of the Bowden wire device and the sheathing of the Bowden wiredevice is increased to such an extent that the normal length of thetraction wire 13 of the Bowden wire device is not sufficient to bringthe distal mechanism in its end position in the direction of pushing. Inthis position, the traction wire 13 of the Bowden wire device fills anyclearance that is present in the sheathing of the Bowden wire devicebecause of the extreme curvature of the Bowden wire device.

In order to guarantee full freedom of motion in this extreme position,as well, the quick-acting closure can be pivoted beyond its normal endposition 15″ by the operating personnel—necessarily with the applicationof a higher physical force than usual—, and in spite of being clamped,the traction wire 13 of the Bowden wire device slips out of theattachment in the hole 27 by the amount of this movement exceeding theend position 15″. This slipping out or slipping through can be madepossible by adjusting a corresponding clamping force at the restoringspring and/or by the cooperation of cam and lever 21 and the resultingoverlapping of the hole 27, without limiting the function of the Bowdenwire device, for example by undesired slipping of the wire 13 in thequick-acting closure.

Hereby, an even larger prestress can be exerted upon the Bowden wiredevice and an even larger portion of the wire can be brought into theBowden wire device, so even in these extreme positions of the endoscopeshaft and thus of the Bowden wire device provided inside, the fullfreedom of motion of the mechanism at the distal end is guaranteed.

FIGS. 6 and 7 show how a mechanism in a support device 39 at the distalend of the endoscope can be detached from the head of the endoscope.

For this purpose, it is only necessary for the operating personnel toactuate a quick-acting closure via a key 47 at the head of theendoscope, e.g. at the face thereof in a corner portion of the supportdevice, after the quick-acting closure 3 has been brought into a releaseposition for the traction wire 13 at the proximal end. Here, thequick-acting closure at the distal end can be configured e.g. as arecess of the endoscope head, in which an engagement element in thesupport device 39, which is complementary thereto and which can beactuated by the operating personnel, engages in the position shown inFIG. 6. As shown in FIG. 7, this recess may be configured as a groove 51in a peg 49 projecting in the longitudinal direction and may e.g. extendaround the periphery thereof, so that this peg 49 can engage acorresponding recess in the support device 39. When the support devicehas been put on (FIG. 6), an engagement element 53 which can be actuatedfrom outside by the operating personnel via the key 47 engages thisgroove 51 in a plane perpendicular to the longitudinal axis of the peg49 so that the support device 39 is fixedly secured to the head of theendoscope. For this purpose, the engagement element 53 may be configurede.g. as an apertured plate which is pressed into the direction ofengagement or is prestressed by the force of a spring in such a way thata part of the edge of the hole engages the groove 51 and can bedisengaged from this engagement position via the key 47.

As apparent in FIG. 7, when the support device 39 has been put off, thesheathing of the Bowden wire device can be pulled out at the distal endof the endoscope at least partially or entirely like the traction wire13 of the Bowden wire device if a channel of the Bowden wire deviceexists. As illustrated in FIG. 7, the rear wall of the support device 39facing the head of the endoscope forms a stop in the pushing directionopposite to the distal end of the sheathing of the Bowden wire device.Thus, apart from a fixed screw connection, the necessary connectionbetween the sheathing of the endoscope and the endoscope for fasteningthe sheathing of the Bowden wire device in the longitudinal directioncan also be achieved by simply inserting the support device 39; thesheathing of the Bowden wire device is limited in the direction ofpulling at the proximal end by a stop which is not shown in greaterdetail and is limited in the direction of pushing at the distal end bythe rear wall of the support device 39 and is thus securely fixed in itslongitudinal direction.

FIG. 8 shows another embodiment according to the invention, in which thepivoting movement of the operating lever 19 is transformed into amovement in the longitudinal direction of the traction wire 13 of theBowden wire device via the lever or the rod 11. For this purpose, asapparent from FIG. 9, the lever 11 is eccentrically mounted with one endthereof on the operating lever 19, e.g. by means of an axle 79 or abolt, such that it is rotatable about an axis which is perpendicular tothe plane of the drawing; with the other end, it is mounted on a partialportion of a slide 55 projecting outside e.g. by means of a screw 77 insuch a way that it is rotatable about an axis perpendicular to the planeof the drawing. Thus, when the lever 19 is turned in the direction B inthe longitudinal direction of the traction wire 13 of the Bowden wiredevice, the slide 55 is moved out of the proximal end 3 of the endoscopeand is moved into it when the lever 19 is turned in the oppositedirection.

Here, by arranging the eccentric rod 11 correspondingly or by thedistance of its mounting position 79 from the axis of rotation of theoperating lever 19, the maximum movement or working area of the slide 55can be selected to be larger than the actual movement area of thetraction wire of the Bowden wire device or of the mechanism at thedistal end of the endoscope connected therewith. Thus, a prestress canbe exerted on the Bowden wire device as described above in connectionwith the first embodiment.

In the second embodiment shown, the quick-acting lever 3 which ispivotable or displaceable in the longitudinal direction of the tractionwire 13 of the Bowden wire device is equipped with a clamping gripper61, which can be clamped by means of a clamping element e.g. in the formof a clamping nut 67 in order to fixedly secure the end of the tractionwire 13 guided in the clamping gripper 61 in the slide 55 in thelongitudinal direction.

As illustrated in FIG. 8, the slide 55 may be configured to besubstantially cylindrical and may comprise a projection shaped like theweb of a key at its outer periphery which extends in the longitudinaldirection at least over a part of its length. This slide 55 is locatedin a slot-shaped bore 57 at the proximal end of the endoscope in thelongitudinal direction of the traction wire 13 of the Bowden wiredevice; the inner dimensions of this bore regarding the cross-sectionthereof are complementary to or slightly larger than the outerdimensions of the slide 55 so that the slide 55 can be moved easily inthis bore 57 in the longitudinal direction of the traction wire 13 ofthe Bowden wire device.

For receiving the traction wire 13 of the Bowden wire device, thecylindrical portion of the slide 55 comprises a recess e.g. in the formof a bore in its end oriented in the distal direction, whose innerdimensions are large enough to receive the end of a Bowden wire device,e.g. a cylindrical projection of the housing, which serves as a stop oras an attachment for the sheathing of a Bowden wire device. In order toobtain a sealing effect that might be desirable, a sealing element—e.g.in the form of an O-ring—may be arranged between the inner wall of thebore of the slide 55 and the end of the Bowden wire device, whichsealing element is optionally fixedly received in a ring-shaped recessof the bore of the slide 55 or, as shown in FIG. 8, in a ring-shapedrecess at the end of the Bowden wire device. At the other end of theslide 55 projecting from the proximal end 3 of the endoscope, there is arecess, e.g. in the form of a bore, extending in the longitudinaldirection of the traction wire 13 of the Bowden wire device as areceiving portion for a clamping gripper 61. As illustrated in theexample, this bore may be limited in its depth, so the slide 55comprises a mid-portion with a bore having a smaller diameter than thesebores and having at least a slightly larger diameter than the outerdiameter of the traction wire 13 of the Bowden wire device.

Hereby, it is possible to insert the slide 55 into the receiving portion57 for the slide at the proximal end 3 of the endoscope; the proximalend of the traction wire 13 of the Bowden wire device moves through therecesses in the longitudinal direction inside the slide 55 and at leastpartly projects into the bore at the proximal end of the slide 55. Inorder to fix the end of the wire, the clamping gripper 61 is insertedinto this bore, which receives the end of the traction wire 13 of theBowden wire device in its central bore 63. In order to make it easier tointroduce the end of the traction wire, the clamping gripper 61 maycomprise a cone-shaped broadened portion at its opening oriented in thedistal direction. At the proximal end, the substantially cylindricalclamping gripper 61 comprises a cone-shaped head 65 with e.g. fourlongitudinal slots. If a force is exerted onto this cone-shaped head 65from outside, the slots make it possible to reduce the inner bore andthus to clamp the portion of the traction wire 13 located therein. Asillustrated in the embodiment serving as an example, the force may beexerted by a clamping element e.g. in the form of a clamping nut whichcomprises a bore with a conical end or bottom, so the clamping grippercloses around the end of the traction wire 13 of the Bowden wire deviceif this clamping nut is pushed onto the cone-shaped head 65 of theclamping gripper in the longitudinal direction of the traction wire 13of the Bowden wire device. The edge at the face of the proximal openingof the slide 55, which engages behind a peripheral shoulder of the conehead 65, serves as a limiting stop acting against this force in thedistal direction. Likewise, however, it would be conceivable to form thelimiting stop between the end of the clamping gripper 61 opposing thecone-shaped head 65 and the bottom of the bore at the proximal end ofthe slide 55.

As illustrated in FIG. 8, the projecting length of the end of thetraction wire is to be selected such that, on the one hand, it can atleast be fixedly enclosed by the clamping gripper 61 and on the otherhand, it only projects from the clamping gripper to such an extent thatthe clamping nut 67 can be screwed on without squeezing the end of thewire. For this purpose, the clamping nut 67 may comprise a recess in theform of a bore which exceeds beyond the conical bottom in order to offera larger receiving portion for the end of the traction wire of theBowden wire device. If a sealing effect is desired between the tractionwire 13 and the sheathing of the Bowden wire device, this bore does notgo through the clamping nut 67, as shown in FIG. 8; the thread portionbetween the inner thread of the clamping nut 67 and the outer thread ofthe proximal end of the slide 55 may comprise a sealing element e.g. inthe form of an O-ring 71.

Like in the first embodiment, with this embodiment, too, it is possibleto exert a prestress onto the Bowden wire device; changing the prestressand thus the working area defined by the end positions 15′, 15″ is ofcourse also possible during an operation. For this purpose, it is onlynecessary to loosen the attachment unit in the quick-acting closure 3,i.e. the clamping gripper 61, by loosening the clamping nut 67, or toloosen the lever 21 by actuating the turning knob 29 and to fix themagain in a locking position different from this position inside oroutside the previous working area by screwing on the clamping nut 67 orby lowering the lever 21 by actuating the turning knob 29.

In practice, this change of the working area already described abovemeans that, in a way, the traction wire 13 of the Bowden wire device isgrasped again, which can be done in both directions, so even in extremesituations, in which the position and thus the effective length of thetraction wire 13 of the Bowden wire device in the endoscope changes dueto extreme distortion, curving, bending etc. of the shaft and/or thehead of the endoscope, one can react by correspondingly changing oradjusting the new working area.

FIG. 11 shows how an irrigation cap 81 can be placed, e.g. screwed, ontothe end of the slide 55 projecting proximally for cleaning purposes;again, a sealing element 83 between the inner thread of the irrigationcap and the outer thread of the end of the slide ensures theliquid-tightness that is required for sufficient irrigation pressure.Thus, like in the first embodiment, it is possible for the operatingpersonnel, e.g. a doctor or a doctor's assistant, to excellently cleanthe Bowden wire device and, particularly if the entire Bowden wiredevice is removed, the entire channel of the Bowden wire device withouthaving to consult maintenance personnel or technicians, which would beexpensive and time-consuming.

Instead of the type of attachment illustrated or instead of the clampinggripper 61 shown, it is of course also conceivable to use other types ofattaching means which are displaceable in the longitudinal direction ofthe traction wire 13 of the Bowden wire device, e.g. a clamping gripperwhich is configured to be cone-shaped in the distal direction and whichis pressed into a conical bore at the proximal end of the slide 55.Likewise, instead of a clamping nut 67, other clamping elements such asengaging levers, springs or the like are conceivable, too, which actupon the clamping gripper in the corresponding direction with a forceclosing the clamping gripper.

What is claimed is:
 1. A flexible endoscope comprising: (a) a firstquick-acting closure located at a proximal end of the endoscope andadapted to be displaceable within a closure working area between firstand second closure end positions, the closure working area defining atraction wire working area for a traction wire of a Bowden wire deviceassociated with the endoscope; (b) an attachment unit connected to thefirst quick-acting closure for selectively detaching the traction wirefrom the first quick-acting closure and attaching the traction wire tothe first quick-acting closure; (c) a positioning structure associatedwith the first quick-acting closure and attachment unit, the positioningstructure defining a locking position of the first quick-acting closurein which the attachment unit can be actuated; and (d) a mechanism at adistal end of the endoscope operatively connected to the traction wire,the mechanism being detachable from the remainder of the endoscope. 2.The endoscope of claim 1 wherein the locking position is remote from thefirst and second closure end positions.
 3. The endoscope of claim 1wherein the positioning structure includes an operating element forsimultaneously actuating the attachment unit while defining the lockingposition of the first quick-acting closure.
 4. The endoscope of claim 3wherein the operating element comprises a turning knob connected to acam for actuating the attachment unit.
 5. The endoscope of claim 3wherein the operating element includes a recess located along a portionof a periphery of the operating element, the recess adapted to beengaged by an engagement element connected at the proximal end of theendoscope.
 6. The endoscope of claim 1 wherein the attachment unitincludes a lever biased to exert a predetermined clamping force on thetraction wire.
 7. The endoscope of claim 1 wherein the firstquick-acting closure comprises a clamping device which is displaceablein the longitudinal direction of the traction wire.
 8. The endoscope ofclaim 7 wherein the clamping device comprises a slide with a clampingelement and clamping gripper, the clamping element and clamping gripperoperative to clamp the traction wire.
 9. The endoscope of claim 1further comprising an externally operable second quick-acting closurefor selectively securing the mechanism at the distal end of theendoscope and releasing the mechanism from the distal end of theendoscope.
 10. The endoscope of claim 9 wherein the second quick-actingclosure comprises a snap-fit or locking closure.
 11. The endoscope ofclaim 9 wherein the mechanism at the distal end of the endoscope ismounted in a support device connected to the remainder of the endoscopeby the second quick-acting closure to provide a distal limiting stop forsheathing associated with the traction wire, so that, the sheathing isremovable from the endoscope when the support device is detached fromthe endoscope.
 12. The endoscope of claim 1 wherein the firstquick-acting closure is moveable beyond its second end position to allowthe end of the traction wire connected to the first quick-acting closureto slip through, and thereby release from, the attachment unit.
 13. Aflexible endoscope having a proximal control end and a distal end towhich a mechanism is attached, the mechanism being actuated via atraction wire of a Bowden wire device associated with the endoscope, theendoscope comprising: (a) a first quick-acting closure located at theproximal end of the endoscope and adapted to be displaceable within aclosure working area between first and second closure end positions; and(b) an attachment unit connected to the first quick-acting closure forselectively detaching the traction wire from the first quick-actingclosure while the endoscope is in use and reattaching the traction wireto the first quick-acting closure to redefine a working area for thetraction wire.
 14. The endoscope of claim 13 wherein the firstquick-acting closure comprises a clamping device which is displaceablein the longitudinal direction of the traction wire.
 15. The endoscope ofclaim 14 wherein the clamping device comprises a slide with a clampingelement and clamping gripper, the clamping element and clamping gripperoperative to clamp the traction wire.
 16. The endoscope of claim 14wherein the clamping device comprises a closure member pivotallyconnected to the proximal end of the endoscope, a lever pivotallyconnected to a distal end of the closure member, and a mechanism forpivoting the lever with respect to the pivot member to provide aclamping action for the traction wire between the lever and closuremember.
 17. The endoscope of claim 13 further comprising an externallyoperable second quick-acting closure for selectively securing themechanism at the distal end of the endoscope and releasing the mechanismfrom the distal end of the endoscope.
 18. The endoscope of claim 17wherein the second quick-acting closure comprises a snap-fit or lockingclosure.
 19. The endoscope of claim 17 wherein the mechanism at thedistal end of the endoscope is mounted in a support device connected tothe remainder of the endoscope by the second quick-acting closure toprovide a distal limiting stop for sheathing associated with thetraction wire, so that, the sheathing is removable from the endoscopewhen the support device is detached from the endoscope.